Under typical solid oxide fuel cell (SOFC) operating conditions, an oxide scale layer inevitably forms on the surface of ferritic stainless steels. If the resulting scale/metal interface is structurally weak, spallation, peeling, or delamination can occur along the scale/metal interface. This can lead to degradation of interconnect performance and reduction of useful stack life.
To improve scale adhesion between the oxide scale and the steel alloy, various coating applications have been developed and employed. These coating applications include treating the alloys with oxygen active elements or adding a rare earth element to certain coatings. Although these techniques have been proven to improve scale adhesion, they eventually result in oxide scale growth and serious cell performance degradation. Therefore, a new approach is needed to prevent delamination/spallation of the oxide scale on the surface of ferritic stainless steels.